About 13 million young adults (ages 20-39 years) have high cholesterol and about six million have high blood pressure. Recent treatment guidelines have discouraged treatment of high blood pressure or high cholesterol in young adults. This is particularly true of cholesterol treatment guidelines, which are based on short-term (ten year) risk for cardiovascular disease. However, evidence is accumulating that high blood pressure or cholesterol in the young adult years is a strong predictor of later life cardiovascular disease, even after accounting for later life risk factors levels. For this project,we propose to build on this evidence by incorporating life course, age-related risk factor trajectorie and impact of young adult risk factor exposures into a microsimulation model of cardiovascular disease risk in young adults. We have assembled a team of experts in cardiovascular disease epidemiology, biostatistics, health economic evaluation, and computer simulation modeling in order to evaluate the incremental value of treating and controlling high blood pressure or cholesterol in U.S. young adults. We aim to use this expertise and these methods in order to: ? Estimate the potential health benefits (life years gained) of early high blood pressure and cholesterol treatment and control during young adulthood, accounting for avoided cumulative atherosclerotic damage from early life exposures to these risk factors, and ? Project the potentil health benefits of early blood pressure and cholesterol treatment and control in young adults with pre-diabetes from 2015 to 2050. We hypothesize that treatment and control of high blood pressure and cholesterol before age 40 years would yield superior lifetime gains in quality-adjusted life years compared with controlling BP and cholesterol according to 10-year risk after age 40 years. However, we anticipate that these benefits will be very sensitive to adverse event rates and any potential quality of life decrement associated with years of adhering to healthful lifestyle choices or taking preventive medications on a daily basis. Relevance: The results of this study may change the way patients, health care providers, payers, and clinical guideline makers perceive CVD risk and the potential for early primary prevention in young adults, and may eventually contribute towards improved lifetime cardiovascular health in U.S. adults. The results have the potential to influence modifications to clinical practice guidelines and encourage worksite-based and other prevention programs targeted at young adult cardiovascular health promotion.